BMJ - Alzheimer's & Benzodiazepines

"Benzodiazepine use and risk of Alzheimer’s disease: case-control study"

"Conclusion
Benzodiazepine use is associated with an increased risk of Alzheimer’s disease. The stronger association observed for long term exposures reinforces the suspicion of a possible direct association, even if benzodiazepine use might also be an early marker of a condition associated with an increased risk of dementia. Unwarranted long term use of these drugs should be considered as a public health concern."  

http://www.bmj.com/content/349/bmj.g5205